Printing-telegraph system



y 7, 1929- G. s. HILTZ ET AL 7 1,711,498

- PRINTING TELEGRAPH SYSTEM Filed March 21, 1928 4 Sheets-Sheet 1 &

y 7, 1929- G. s. HILTZ ET AL 1,711,498.

PRINTING TELEGRAPH SYSTEM 4 Sheets-Sheet '2 Filed March 21, 1928 G. S. HILTZ ET AL PRINTING TELEGRAPH SYSTEM May 7, 1929.

4 Sheets-Sheet 5 'Filed March 21, 1928 xxx om in Nu I l I l Patent ed May 7, 1929.

UNITED" STATES PATENT; OF ICE.

Gnonen .s. nmrz, or nnooxnnr, N'Ewxonx', AND WILLIAM F. roman, or" 110- BOKEN, new .mnsny, AssIGNons T s'rocx cuoruron rmnemn commit,

or NEW YORK, N. Y-., A oonrona'rron or NEW YORK.

PRINTING-TELEGRAPH sxsrnm,

Application filed Harch 21, 1928. Serial No. 263,863.

forations being in transverse alignment) which passes between cooperating contacts in said controlling circuits. Since the tape is non-conducting no current flows from one contact to another except when a perforation is in registry with the two. vThe latter can then close, permitting current to flow in the circuit with which the particular contacts are associated. More especially our present invention pertains to .the aforesaid contact mechanism, and its chief object is to provide convenient, effective and reliable contact mechanism of the mercury type, that is, mechanism in which a body of mercury serves as a contact common to a plurality of insulated contacts, the mercury being adapted to pass through the perforations in the tape and thereby engage singly the cooperating contacts on the opposite side of the tape. 1 A further object is to provide simple and durable mechanism for the purpose, positive in operation and capable of use for long periods without the necessity of fre- -quent repair or critical adjustment. To these and other ends the' invention comprises the 1 novel features of construction and combinations oflelements hereinafter described.

7 The invention can be embodied in a .con- 'side'rable variety of forms, and of these we have selected for description herein the one whicltat the present time is believed to exhibit the invention in its most convenient and effective form. This embodiment is designed particularly for use in the printing telegraph system described in our 'copending application' Serial No. 110,850, filed May' 22,

I 1926, in which the receiver is of the so-called ticker type printing on a paper tape under the controlo current impulses of-alterna'ting polarity the number of which in each group or train is controlled at the transmitter by asunflowe'r' comprising an annular series of insulated contacts a'nd a. revolving wiper which passes over the contacts in succession and is synchronized with a pole-changing switch in such manner that as the wiper passes off one contact and onto the next the current n the transmission circuit is reversed- 1n polarity. The system thus briefly outlined may also include the so-called mag netic shift mechanism described in our copendmg application Serial N 0. 144,230, filed, October 26, 1926,.and the preferred form of our present invention is adapted to the usev of the mechanism mentioned as will be explained more fully hereinafter." Referring now to the acco inpa'nying draw.- mgs: I v

Fig. 1 is a wiring diagram showing theelectrical connections of the contact devices and so much of the wiring of the transmission system as seems useful in understanding the function of the perforated tape incontrolling the transmitter and thedistant re: ceiver. v

Fig. 21s a plan View} of-the preferred form of contact mechanism.

Fig. 3 is a cross section on the line 3.-3 of Fig. 2, showing the two mercury contacts, the transversely aligned fixed contacts above the mercury contacts and in cooperative relation to the latter, and the standpipes for putting a head on the mercury to cause the same to rise through theperforations in the tape. I

Fig. 4 is a section on the line 4-4 of Fig. 2. Fig. 5 is a side view of the contact mechanism, showing the electromagnetic devices which pass the perforated tape step-by-step between the mercury contactsand the fixed as is also the shift magnet 18 which'determines which of the two receiver type wheels (not shown) will make the imprint, as ex- 10 pl-ained -in our copending'application Serial the shaft to bearrested without stopping the motor. Slip ring has an insulating, segments 2O which, as the shaft revolves, 10

lifts brushes 22, 23 out of contact alternately.

In the position shown, current flows from grounded brush 21 through magnet 25 of the pole-changing relay 26 to the current-supply main 27. The armature of the relay, represented by contact 28, is thus attracted by magnet 25 and engages contact 29, and positive current then flows from main 27 through wire 30, contacts 29, 28, armature 31 of the repeat? magnet 32, wire- 33, relay 108 (which controls the feed of the perforated .tape through the transmission-controlling contact mechanism), resistance v35 and line wire 17 to the ticker press-relay 14. When the rotation of shaft 24 carries insulating segment 20 into cooperation with brush 23, brush 22 is then in engagement with ring 20 and current flows through magnet 36 of the pole-changing relay 26. Armature 28 is swung over to contact 37, whereupon negative curren flows from main 38 through wire 39, contacts 37 and 28, and thence through the path traced above, to the receiver. In this way current impulses of rapidly alternating polarity are sent over the transmission line as long as shaft 20 :evolves. These impulses through the escapement magnets 15, 16 control in the usual way the rotation of the receiver type wheels (notshown) to bring the desired character to the rintin csition whereupon the shaft 24 is arrested. The impulse last sent (of whatever polarity it may e) is thus prolonged, thereby energizing the slow-acting relay 14 which then draws its armature over and closes the local circuit of the press magnet 11. The latter then actuates the receiver platen, not shown. As long as the shift relay magnet" 40 is deenergized resistance 35 remains in, the transmission circuit; the current'through shift magnet 18 is therefore too weak to energize "the latter magnet, and hence all the imprints at the receiver are made from the same type wheel. When, however, the circuit of magnet 40 is closed (as hereinafter described.) the armature 41 israised, thereby laying a shunt or short circuit across the resistance, thus strengthening the line current to a' value suihcient to energize the shift magnet which then causes the next imprint to be made from the othertype wheel.

cient number 0 current im ulses have been sent to bring the desired c aracteron the receiver type wheel to the printing position) p .K,L,M,N,F,andsoon. Still referrmg to-Fig. .1', the shaft 24 1s arrested at the roper instant (when a. sufiiby an electromagnetic clutch or brake 42,

which may be of a well known type, connected to ground and to the armature 42 of a relay 43. The latter is connected to main 38 through lower mercury contact 44 and upper pin contacts 45, 46, 47 '48. Whenever current flows through contact 44 and any one of the four upper contacts the relay is energized and swings its armature over against contact 49, whereupon current flows in the clutch local circuit. gized, the clutch arrests the shaft 24 and the current then flowing continues to flow, with the results described above.

The transmitter is also provided with a sunflower 50. Fig. 1, comprising an annular series of twenty-eight insulated contacts, twenty-six of which are shown marked with the letters of the alphabet and two, diametrically opposite each other, are shown marked with dots, representing periods. The upper Being thus cnerof these two is termed herein the letters period contact and the lower as the figures period contact. The sunflower cont-acts are connected to form seven sets of four each, one

contact of each set being connected to one ing a set. Similarly, contacts G, F, S,Z

are connected together and so form another set.- Each set is also connected toone of seven-pin contacts 51, 52, 53, 54, 5o, 56, 57, above the mercury contact 59, described hereinafter. Thus the set composed of contacts G, F, S, Z is connected to pin contact 57, and that composed of letters periodVH, figures period and T, is connected to pin contact 51. Inside of the outer series of contacts there are four insulated contacts 1, 2, 3, 4, each spanning'seven contacts of the outer series and connected to the pin contacts 45, 46, 47, 48 respectively. The sunflower also has a wiper 58, fixed on a shaft 58 which is connected with the motor-driven shaft 24 b reducing gearing (not shown) of such ratio that the wiper makes one revolution for each fourteen revolutions'of the shaft 24. Since two current impulses are transmitted in each revolution of the latter shaft, it will be seen that twenty-eight impulses are sent in .each revolution of the wiper 58. The latter has two electrically connected fingers bearing one on the outer contacts andthe other on the inner, so that as the wiper revolves from the position shown in Fig. 1 it connectsvinner contact 1 to outer contaets A, B, O, D, E, G, in succession, then contact 2 to contacts H, 1,

Sup ose now that the letter A having been rint'el at the receiver it is desired to print Tracing the connections it will be seen that outercontact D is connected to pin contact 55 and inner contact 1 to pin contact 45.-

Hence connection is made (as described hereinafter); between mercury contact 59 andpin 55 only, and between mercury contact 44 and pin -45"o1ily. (If, asin the present embodiment, the letters are on the type wheel which prints only when stron current is transmitted, that is, when t e resistance 35- is shunted out of circuit by energization of the.

'relay 40, connectionmust also be made-between contacts 44 and 66, in series with the relay and battery 40.) Now as the wiper moves counterclockwise the pole-changing switch or commutator sends alternating imarrests shafts 24 and 58. Letter D havingbeen printed, suppose that the next letter is 'O. The circuit being broken at contacts pulses to the receiver, whose type wheels follow in unison with the wiper until contact D is reached and type D at the receiver is at the printing position. from main 38 through wire 60, relay magnet 43, contacts 44 and 45, wire 61- to inner sunflower contact 1, across the wiper to outer contact D, thence through wire 62, pin contact 55, mercury contact 59, wire 63, contact 6'8, unison key 64 and wire 65 to main 27 Relay'43, thus energized, closes the local cir-.

cuit of the brake or clutch 42, and the latter 59--55 and 44-45 and made at 5953 and 4447 the clutch is deenergized, shaft 24 rotates and the wiper'58 moves over the sun- 5 aft, with the characters on one in axial alignment with those on the other. Since (in the present instance) each wheel hastwentyeight character spaces each outersunfiower contact corresponds to two characters or character spaces, one on each wheel. In general one wheel has letters of the alphabet and the other carries numerals, fractions, and any s eci'al characters or symbols that maybe desired. When (in the resent system) it is desired to print from t e second wheel,- say a number or a fraction, or a special character,

contacts 44 and 66 are not closed at 'thesame time as the desired character-selecting con- "tacts are closed, and hence resistance 35 is not'shunted' out and weak current is therefore sent over the line as explained above.

It will be readilyseen that accuracy of printing depends upon keeping the receiver type wheels in step or in unison with the sunflower'wiper. If the wheel, gets out of unison, assometimes happens, the: operator Current now flows' 51 is to. be removed. The mercury.

can bring it back into unison by depressing the unison. key 64 to its neutral or mId-po-' .sition. 'This opens the circuit through the clutch relays 43, sothat the clutch cannot be energized even though the other contacts in the circuit-be closed. Hence the sunflower wiper will revolve as long as the key is held in-the position stated, and the receiver type wheels will also revolve until by means (not shown) provided for the purpose at the receiver they are brought to rest automatically with letters period at the printingposition.

The. operator has before him a receiver (not shown herein) in circuit with the distant receiver, and when he observes the type wheels 'Tof his own receiver come to 'rest he depresses key 64 farther, bringing it into engagement with contact 67. On shaft 58 is a'cylinder .69 of insulating material carrying a conducting bar 7 O axially aligned with the tips of the fingers on the wiper 58 and adapted to bridge the two brushes 71, 72 when the.

wiper is on the letters period contact. Brush 72 being connected with mercury contact 44 and brush 71 with the lower contact 67, it will be seen that with key 64 fully depressed current can fiowthrough the clutch I relay 43 when, and only when, the wiper is onthe letters period contact (the upper of the two contacts marked with a dot). Hence when the revolving wiper comes to the contact mentioned current flows from main 38 through wire 60, contact 44, wire 73, brush 72, contact bar 70, brush 71, contact 67, key 64 and Wire 65 to main 27. The clutch relay 43, being thus energized, closes the clutch local circuit and shafts 24 and 58 are arg rested with the wiper on the. letters period contact. This method of coming to unison forms the subject of our copending application filed March 21, 1928, Serial No. 263,364.

Referring now to Fig. 3, the bodies of mercury 44, 59 are the similarlv numbered contacts in Fig. 1, and the-pins 45, 46, 47, 48, 66, 51, 52, 53, 54, 55, 56, 57 are the contacts having the same numbers in the figure last mentioned. The two mercury contacts are I contained in narrow transversely elongated chambers in an insulating block 75 into which the horizontal metal tubes 76,- 77 are snugly fitted. At their ends the tubes are bent to form standpipes 78, 7 9, in which the mercury extends," as shown. When the standpipes are upright the resulting head causes. the mercury in the blocks 75 torise into contact with the down, as indicated in dotted lines, the mercury runs down into them and out of contact. with the'pi-ns thereby preventing escape of the i 1 25 mercury when the tape or the insulatin block we are connected in circuit by means of s rings '80, 81, Fig. 2, having po1nts'82' 83, ig. 3, pressing firmly into recesses int c bosses 84,

85. The perforated tape 100,- Fig. 4, p

pins, but when the standpipes are turned ceiver platen will be shifted to the other type wheel and a letter will be printed.

The tubular mercury containers 76, 77, 3, may be made in two parts, as shown, the

standpipe portions 7 8, 79 being fitted into the ends of the horizontal portions. The former are slotted along one side, forming wln'dows or sight-openings 78 closed byinner glass tubes 79 suitably sealed in place at top and bottom to prevent leakage of mercury.

, Screw-closures or caps 7 9 are provided in the tape to carry minute globules of mercury the ends of the standpipes for easy supply or withdrawal of mercury.

The contact pins 45, 46,47, 48, 66, 51, 52, 53, 54, 55, 5 6, 57, Figs. 1, 3 and 4, are composed of heavy wires, for example copper or brass, and are mountedjn a'two-piecc insulating body 51, and are bent to bring them up through suitable openings in the upper part of the supporting body into 'connection inclividually with a longitudinal row of terminal buttons 86 engaged 87 (shown best in Figs. 2 and 4) for connection with the corresponding sets of outer contacts andthe four inner contacts on the sunflower. The block or body 51, carrying the contact pins,is held in place by screws 51*, Fig. 2, and when these are removed it may be slipped out from under the spring terminals for inspection or repair, etc. The terminals mentioned are mounted on an insulating block 89 supported by pillars 90 on block 75, which, along with the tube-bearings 91, 92, is carried by the top plate or table 93 (see also Fig. 5) of the housing 94 in which the actuating solenoids of the punching mechanism are located. As the tape passes between the upper and lower contacts to present successive groups of perforations thereto there is a tendency for away with it. In order to save any mercury thus carried away the block 75, Fig. 4, is provided with a recess or receiving chamber 95 over which the tape passes and into which the mercury drops and passes thence through an outlet or escape passage 96 to a funnel 97, open at the bottom. From the latter the mercury drops into a small receptacle not shown.

Thecontrol tape is drawn through the con- I tact mechanism step by step by a sprocket wheel or roller 98, Figs. 2, 4, 5, cooperating with a central longitudinal row of holes in the tape. This roller, located at the outlet or dis;

by spung terminals charge end of the contactmechanism, is rotated by a pawl 101 engaging axratchet 102.

The pawl is pivoted on-the rear end of an,

.wise to raise the pawl, and between the fulcrum and the pawl the lever is connected by a link 106 to the core 107 of an actuating solenoid 108. The pawl is heldin engagement with the ratchet by a small coil spring 109, Fig. 5, between the pawl and its actuating lever. Y

The tape is held in engagement with the sprocket roller 98 by a cramp roller 98, and a holding pawl (not shown) may be employed in cooperation with the ratchet 102 if necessary or desirable, to prevent backward rotation of the ratchet and sprocket when the actuating pawl is advanced over the ratchet by the spring 105.

To enable the operator to advance the tape -manually at will the journal 200 of the sprocket roller 98, Fig. 2, is provided with a pin 201 for engagement with a slotted collar on the adjacent end of a sliding shaft 202 mounted in a suitable bearing 203 and urged outwardly by a coil spring 204 between said bearing and the knurled button 205. The pin 201 can be engaged by pressing the shaft inwardly, whereupon the sprocket roller can be rotated by turning the button.

The relay 32, controlled by'the' normally closed contacts 32, controls the repeating mechanism described in our copending application-Serial No. 110,850, mentioned hereinbefore, to which reference may be made for a detailed explanation. It is sufiicicnt to say here that when a group of transmission controlling perforations in the tape is repe: ted,

to cause the letter or character last printed at' the ticker to be printed again, the repeat mechanism opens and closes vthe contacts 32,

with the result that (as explained in our application aforesaid) the ticker tape is advanced one step and the press magnet is energized without rotation of the ticker type wheel and of the wiper on the transmitter sunflower. I

The solenoid magnet 108, which draws the perforated tape step by step through the contact mechanism, as above described, is controlled by a relay1'08", in the transmission circuit connecting the transmitter and the distant receiver or receivers, as indicated in Fig. 1. The relay 108 is not energized by the rapidly alternating character-selecting impulses sufficiently to actuate its armature but when the final impulse is prolonged (by arrest of the shaft 24 as explained above) to print the character at the receiver the relay is fully energized and closes the local circuit of feed magnet 108. It will therefore be seen that each time the receiver prints 9. character the feed solenoid is energized and the pawl 101 is drawn down, thereby feeding the tape forward one ste and bringing the next is raised b the spring 105 into osition for the next feeding operation. .Pre erably the feed of the tape takes place just after the printing and hence the relay 108 is made slightly slower in action than the relay 14 which con- 1 trols the press magnet 11.

' Preferably the perforated tape 100 comes to the contact mec anism directly from the mechanism which punches the perforations in the tape, as for example the mechanism illusl trated in Fig. 4. This mechanism is de scribed and claimed specifically in our copianding, application Serial No. 263,362, filed arch 21, 1928, and'hence need not be described in detail herein.- It will be suflicient here to explain that it comprises a transverse row'of punches 110, cooperating with a dieplate 115 and actuated by levers 119 which are themselves actuated by solenoids 123. The

- tape is drawn through the punching'niechanism by 'a sprocket roller 124, rotated step-bystep in harmony with the punching devices by any convenient mechanism, not shown, as for example the mechanism described in our aforesaid application Serial No. 263,362.

. the contact. devices.

Since the tape is fed ositively through the contact mechanism an is also fed positively through the punching mechanism, it will be seen that to prevent tearing the tape the feed pastthe contacts should be no faster than the delivery from the punching-devices. On

the other hand, if the punching mechanism is' operated under, manual control of the operator he may not keep up with the contact/ feed at alltimes, and to prevent damage to the tape under such circumstances we control the contact feed in such way that the feed will cease if for any reason the tape is not supplied to'it' fast enough. For this purpose the local circuit of the feed magnet 108 is provided with a pair of contacts 145., 146, Figs. 1

and 4. The latter contact, which is pivoted and normall held on the other by a spring, not shown, as a finger .147 underlying the tape 100 between the sprocket roller 124 and So long as the operator keeps the punching mechanism working fast enough to maintain at leasta small'loop of tape above the fin er 147 the contact feed continues to operate, ut should the punching op- 'eration be slowed up too long the tape, ad-

vanced at a faster rate by the contact feed, will engage the finger and by downward pressure thereon rock the contact 146 out of en-' gagement with the contact 145, thereby breaking the circuit of feed magnet 108 before all the slack between the two mechanisms is taken up. It is then necessary for the operator to speed up the punching operation,

, system, in combination, a

thereby releasing the contact 146 .and permit-- ting'it to close again on contact 145.

It is to-be understood that the invention is I not limited to the specific construction herein cury reservoir adapted to be closed by the tape, an insulating body spaced from the first and having a transverse row of contacts for engagement with mercury protruding through perforations in the tape, and means operable to. put a hydrostatic head on the mercury in said reservoir or to head, at will.

I 2. In a tape-controlled printing telegraph system, in combination,-mechanisin for a'd vancing a perforated tape longitudinally, a body of insulating material adjacent to the path .of the tape and having a transverse mercury reservoir ada ted to be closed by the tape, an insulating hbdy spaced from the first and having a transverse row of contacts for engagement with-mercuryprotruding through perforations in the tape, and means operable 'to put a hydrostatic head on the mercury in said reservoir or to relieve such head, at will, saidmeans comprising a mercury container communicating with said reservoir and adapt ed to be raised and lowered relatively to the reservoir. I

3. In a tape-controlled printing telegraph system, in combination, mechanism for advancing a perforated tape longitudinally, a body of insulating material adjacent to the path of the tape and having a transverse merrelieve such cury reservoir adapted to be closed by the ody spaced from the first 4. In a tape-controlled printin telegraph system, in combination, a body 0 insulating material havln a transverse mercury'reservoir adapted to e closed by a tape passed over the same, an insulatin body spaced from the first for passage. of t e tape and having a transverse row of contacts for engagement with mercury protruding through perforations in the tape, and a horizontal tubular .mercury'con'tainer communicating with the mercury reservoir, pivoted to be rocked on its axis and having an angularly extending rtion.

I 5. In a tape-controlled rinting telegraph hody of insulating spring terminals releasabl material having a transverse mercury reservoir adapted to be closed and opened by a ,perforated ta passed over the same, a contact arrange to be engaged by mercury emerging from the reservoir through a perfo- -ber arranged adjacent to the mercury reservoir to permit the passage of the tape and having a contact in position to be engaged by mercury protruding through a perforation in the tape, means for holding the insulating member in position and permitting removal of the-same at will, and means for preventing escape of mercury from the reservoir when the insulating member is to be removed.

7 In a tape-controlled printing telegraph system, in combination, an insulating body having a transverse mercury reservoir, an insulating body removaoly mounted adjacent to the said body to permit passage of a perforated tape between the two, a plurality of contacts mounted in said member to cooperate with a body of mercury in said reservoir under the control of the tape, a plurality of terminals carried by said member and connected with said contacts. and a plurality of terminals releasably engaging the first named terminals for connecting the same with a plurality of circuits.

8. In tape-controlled printing telegraph. system, in combination, a fixed insulating body and a removable insulating body arranged to permit the passage of a perforated tape between the two, transverse contacts in said bodies adapted to be selectively closed through perforations in such tape, fixed terminals arranged on the removable body and connected with the contacts in said body, and engaging the fixed terminals for connecting the latter in a plurality of circuits and permitting removal 0 the removable bod 9. In a tape-.contro led printing telegraph system, in combination, transverse upper and lower contacts spaced apart for passage'of a perforated tape therebetween, a group of terminals connected with the upper contacts,

a group of spring terminals, a support for the upper contacts and their terminals removably positioned with the fixed terminals in releasable engagement with the spring terminals, and a support for the spring terminals.

10. In a tape-controlled printing telegraph system, in combination, a transverse row of insulated contacts having terminals, a removable support for said contacts and terminals,

a longitudinal row of spring terminals releasably engaging the first terminals, a support for the sprmg terminals, and contact means adjacent to said insulated. contacts to permit passage of a perforated control tape.

11. In a tape-controlled printin telegraph system, in combination, a body of insulating material having a contact exposed at thesurface of said body, mechanism for passing a perforated tape bver said contact, and a body of insulating material spaced from the first to permit passage of the tape and having a mercury reservoir adapted to be closed by the tape and permit the mercury to extend through perforations in the tape into engagement with the contact, said body having also a recess beyond the contact to receive mercury "carried from the reservoir by the tape.

12. In a tape-controlled printing telegraph system, in combination, a body of insulating material having a contact exposed at the surface of said body, mechanism for passing a perforated tape over said contact, and a body of insulating material spaced from the first to permit passage of the tape and having a mercury reservo r adapted to beclosed by the tape and permit the mercury .to extend through perforations in the tape into engagement with the contact, said body having also means for recovering mercury carried from the reservoir by the tape.

13. Ina tape-controlled printing telegraph system, in combination, a reservoir adapted to contain mercury for protrusion of mercury through perforations in a tape passed across the reservoir, and a receptacle beyond the reservoir and underlying the path of the tape, into which mercury carried from the reservoir by the tape pcrim'ations may drop.

14. In a tape-controlled printing telegraph system, in combination, an insulating body having a mercury reservoir from which mercury may protrude into perforations in a tape passing across the reservoir, said body having also a mercury receiver underthe tape into which mercury may fall which has been carried away from the reservoir by the tape perforations.

15. .In a printing telegraph'system, in combination, transmitting mechanism adapted to send current over a transmission line: a receiver controlled by current so sent; and means for controlling the current sending operation of the transmitting mechanism;

said controlling means including a plurality of control circuits and a plurality of contacts therefor arranged ingroups, confined bodies of mercury associated with the respective groups of contacts and adapted to flow into engagement with the latter; mechanism for feeding an insulating perforated control tape between said contacts and the associated bodies of mercury to prevent such engagement except through the perforations in the tape; and actuating means for said feed-ing mechanism, under the control of current sent over the transmission line to maintain the feed of the tape in harmony with the operation of the receiver.

i 3 16. In aprinting telegraph system, in combination, transmitting mechanism adapted to sendf'current over a transmission line; a receiver controlled by current so sent; and means for controlling the current sending operation of the transmitting mechanism;

said controlling means including a plurality of control circuits and a plurality of contacts therefor, a confined body of mercury associated with said contacts and adapted to'flow into engagement with the latter; mechanism for feeding an insulating perforated control tape between said contacts and the associated body of mercury to permit such engagement only through perforations in the tape; and

actuating means for said feeding mechanism,

under the control of current sent oi er the transmission line to maintain the feed of the tape in harmony with the operation of the receiver.

17. In a printing telegraph system, in combinatlon, transmitting mechanlsm adapted to send current over a transmission line; and

means for controlling the current sending operation of the transmitting mechanism; said controlling means mcludlng a plurality of control circuits, and a plurality of con 18. In a prmtlng telegraph system, in combination, a transmitter having a sunflower, a wiper traversing the same, a commutator operating in harmony with the wiper to send current impulses over a line, and electromag netic means for arresting the commutator and wiper with the latter on a selectedcontact of the sunfiowe'rj'a plurality of stationary contacts connected with the sunflowerto control said arresting ineans; and a confined bod of mercury under a head for causing it to owinto engagement with the stationary contacts under the control of a perforated tape to complete a control circuit for said arresting means.

19. Ina printing telegraph system, in combination,-'a transmitter having a sun'- fiower, a wiper traversing the same, a com mutator operating in harmony with the wiper to send current impulses over a line,

and electromagnetic means for arresting the commutator and wiper with the latter on a selected contact of the sunflower a plurality of stationary contacts connected with the sunflower contacts to control said arresting means; an insulating body inwhich the stationary contacts'are arranged side by side;

an insulating" body having a chamber containing mercury and providedwith' a slot permitting the mercury to engage the stationarycontacts to complete a control cir cuitfor said arresting means, said insulating bodies permitting the passage between the same of a perforated tape to prevent engagement of the mercury with said stationary contactsexcept through perforations therein.

20."In a printing telegraph system, means for closing and opening a plurality of control circuits, comprising in combinationfa row of insulated contacts arranged side b side, aninsulating body having a mercury chamber below said contacts, said body being apertured to permit mercury to-engage the contacts, said insulating body permitting passage of a perforated. tape between the same and said contacts to permit the mer- --cury to engage a contact only when a perforation isimmediately below the contact.

.21. In a printing telegraph system, means for closing and opening a plurality of control circuits, comprising in combination, a body of insulating material, a row of contacts arranged side by side in said body, an insulating body below the first and having a .mercury chamber, said body being apertured to permit mercury'to' rise in said slot into engagement with the contacts, said insulating bodies permittingv the passage of a perforated tape between them whereby to permit the mercury to engage a contact only when a perforation is immediately below the contact. p

22, In a printing telegraph system, transmission circuit controlling means, compri'sing incombination, a row of contacts arranged side by side and insulated from each other, an insulating body below said contacts and having a mercury chamber proslot into engagement with the-contacts, said contacts and insulating body permitting the passage of a perforated tapebetween them whereby to permit the mercury to engage a contact only when a perforation is immediately below such contact, and means for putting a hydrostatic head on the mercury to cause the same to rise in the slot.

vided with a slot registering with said row of contacts to permit mercury to rise in said v 23. Ina printing telegraph system, transmission-circuit controlling means, comprising in combination, a row of contacts arranged side by'side and insulated from each other, an insulating body "below said con- ,tacts and having a mercury chamber provided with a slot registering with said row of contacts to permit mercury tor-ise in said" slot into engagement with the contacts, said contacts and insulating body permitting passage of a perforateditape between them whereby to permit the mercury to engage a contact onlywhen a; perforat on is imme-.

lit)

diatel-y below such contact, and a head-producing and relieving standpipe pivotally connected with said mercury chamber.

24:. In a printing telegraph system, contact mechanism comprising in combination,

an insulating body; a horizontal row of contacts arranged side by side therein; an insulating body below the first havingseparated mercury chambers," one chamber having a slot registering with a group of said contacts to permit engagement thereof by mercury rising in the slot, the other chan'iber having a slot registering with another group of said contactsfor like operation;'said insulating bodies permitting the passage therebetwecn of' an insulated circuit-cmitrolling tape having successive transverse rows of perforations to permit engagement of each mercury body with one or another of the contacts immediately above the same according to the positions of the perforations in the tape; and mercury standpipes pivotally mounted on the second named insulating body and connected with the respective mercury chambers.

25. In a printing telegraph system, contact mechanism con iprising an insulating body having a mercury chamber and provided with an opening in its-upper r-mrtace con'nnunieating with said chamber, a contact'above said opening and engageable by the mercury in said slot through perforalions in an insulating control tape passed between the'same and the contact, and a mercury standpipc pivotally 'mounted on the insulating body and connected with said chamber.

26. In a printing telegraph system, contact mechanism comprising in combination an insulating body, a row of contacts therein having their lower ends exposed; an insulating body having a mercury chamber and provided in its upper surface with a slot registering with said contacts and communicating with the mercury chamber to permit nu-rcury in the slot to engage the exposed ends of said contacts; supporting means for said bodies for the passage of a erforated tape therebetween to control sucl-en agement, and permitting separation o the bodies for insertion of the tape; and a mercury standpipe pivotally connected with the mercury chamber adapted when in upright position to put a headon the mercury in the chamber and when in lower position to drain mercury out of the chamber.

27. In a printing telegraph system, in combination, a body of insulatin material, a row of contacts arranged side by side in said body, an insulating body below the first and having a mercury'chamber provided with a slot registering-with said row of contacts to permit mercury to rise in said slot into engagement with the contacts, said insulating bodies permitting passage of a perforated tape between them whereby to permit the mercury to engage a contact only when a perforation is immediately below such contact, rotary means for feeding the tape, and electromagnetic means for actuating said feeding means.

28. In a printing telegraph system, in 4 combination, a body of insulating material, a row of contacts arranged side by said body, an insulating body below the first .and having a mercury chamber provided with a slotregistering with said row of contacts to permit mercury to rise in said slot into engagement with the contacts, said insulating bodies permitting passage of a perforated tape between them whereby to permit the mercury to engage a contact only side in til) when a perforation is immediately below such contact, a rotary member having teeth for engaging the tape to advance the'same, a ratchet connected with said member to rotate thesame, a awl associated with the ratchet to rotate tie same step by step, and electromagneticmeans for actuating the pawl.

29. A mercury contact mechanism includ ing a plurality of contacts carried by an upper insulating plate, a mercury reservoir thereunder, and spaced therefrom to permit thcpassage of a-perforated insulating ta )e therebctwcen' and means for lowering the level of mercury in said reservoir when replacement of said tape or inspection of said contacts is desired. 7

In testimony whereof we'heret'o afiix our signatures. 

